In the high-end suburb of University Park, 15 minutes east of downtown Sarasota, Fla., there’s a three-bedroom, single-story home within walking distance of the local country club. Attached three-car garage. Screened-in porch. Assessed value: $618,772.

Not the sort of place you’d go to buy a Soviet anti-aircraft system with four automatic 23mm cannons. But records indicate that a ZSU-23, a Russian-built air-defense system deployed by dozens of countries from Armenia to Zimbabwe, was indeed brokered for sale by a company registered at the home. The company is a small defense contracting firm named Atlas International Trading.

The customer in the transaction? That might come as the biggest surprise of all. It was the U.S. government.